Two court rulings dealt a blow to the US state of Arkansas in its attempt to put to death seven inmates within days, BBC reports. 

The first, on Wednesday evening, halted the execution due the following day of Stacey Johnson so he could make fresh DNA claims to prove his innocence.

Moments later, a district judge blocked the use of one of the lethal injection drugs, halting all seven executions.

The pace of executions - originally eight in 11 days - has prompted criticism from rights' groups.

Johnson was convicted of the murder of Carol Heath, who was beaten and had her throat slit in her flat in 1993.

Her two young children were at home at the time.